A growing popularity of the Internet has spurred a rapid growth of Internet websites that promote various products and services to the users. For example, Internet-based shopping websites advertise, recommend, and sell books, clothing items, jewelry items, home goods items, etc. Movie-rental websites distribute copies of movies. News websites market copies of electronic documents, access to newsgroups, access to news media, etc. Game websites promote and sell electronic games, memberships to fan clubs, etc. Music websites sell music files, music media, etc. Travel websites sell airline tickets, vacation packages, etc. Entertainment websites sell tickets to concerts, shows, etc. Websites affiliated with social organizations recommend candidates for a board election, etc. These and many other types of websites attempt to promote their candidate items, objects, services, products, people, and/or other entities to the users.
Regardless of the nature of the candidate items promoted by a website, the candidate items are selected by determining those candidate items that meet specific objectives specified by the website designers or sponsors. For example, one objective may be to maximize the number of sales transacted by the website. In a book-selling example, the objective may be accomplished by recommending, to the users, the books that are bestsellers and that are most likely going to be purchased by the customers. In a travel-package-selling example, the objective may be accomplished by recommending, to the users, the travel packages that are the most popular and are in a highest demand.
Another objective may be to maximize the revenue generated from the sales of products by the website. In the book-selling example, the objective may be accomplished by recommending the books that are not only very popular, but also most expensive. Similarly, in the travel-package-selling example, the objective may be accomplished by recommending the travel packages that are not only in high demand, but also luxurious.
However, in formulating the objectives, the existing recommending systems rely on approaches that merely take into a consideration the candidate items that are presently recommended to the users. In the book-selling example, the system selects and simultaneously recommends, to the user, one or more book candidates, hoping that the objective is met when the user selects and/or purchases one of the simultaneously and presently recommended books.
The approaches described in this section are approaches that could be pursued, but not necessarily approaches that have been previously conceived or pursued. Therefore, unless otherwise indicated, it should not be assumed that any of the approaches described in this section qualify as prior art merely by virtue of their inclusion in this section.